Season 2
Season 2 Olivia, having been taken to William Bell's office in the parallel universe is returned to the prime universe but with short term amnesia, unable to recall her experience there. Massive Dynamic's Nina Sharp directs her to Sam Weiss, a bowling alley manager, who gives her cryptic but helpful advice to overcome her amnesia. Meanwhile, the Fringe division has discovered several shapeshifters - a human/machine hybrid that bleed mercury - have crossed over, but unbeknownst to them, one takes the form of Olivia's partner, Charlie. When Sam's advice allows Olivia to recall what Bell told her, she unwittingly gives this information to the shapeshifter, who calls its agents to use the information to recover the body of Thomas Jerome Newton, an agent for some entity operating from the parallel universe. Nina provides Olivia with cautionary advice, alerting her to a "great war" that Bell postulated would occur between the two universes. During this time, Peter has come to forgive Walter for his past, and Walter has grown accustomed to normal life outside of the institution, but is still troubled by a secret. Newton, using old technology from Walter and Bell's research, are able to pull an entire building from the parallel universe to the prime, and the team races against time to prevent harm when, due to the laws of mass conservation, a building from the prime is pulled to the parallel one. This event forces Walter to try to coax Olivia to recall her Cortexiphan abilities as to identify things affected by the parallel universe. Initially unable to do so, her fear of failure enables her ability, allowing them to save the people within the target building, but also revealing to her that Peter is from the parallel universe. Walter explains to Olivia that in 1985, he and Bell had devised a way to observe the parallel universe, where he found his doppleganger, "Walternate", was also close to losing his son. Though Walter's Peter had passed away, Walternate continued to search for a cure, but missed the telltale sign when the Observer September arrived as his lab. Walter resynthesized the cure and aimed to cross over using untested equipment at Reiden Lake, though stalled by Nina and his lab assistant Clara. Nina tackled him on his way over, losing her arm in the process, while Walter, on the other side, found the cure vial broken. Intent on curing the alternate Peter, he posed as his father and crossed back with Peter, intent to administer the cure at the lab and return Peter. However, on the return, the ice on Reiden Lake broken, threatening to drown both, but they were saved by September, who cautioned Walter "the boy must live". While Walter successfully administered the cure, his wife Elizabeth saw Peter, and Walter realized he could never return Peter to the parallel universe. After Walter reveals this truth, he considers letting Peter know but struggles with how to do so, hoping to seek repentance from God for his actions. Meanwhile, Newton has continued to use Walter's technology to bring into temporary existence elements from the parallel universe. This enables Newton and his agents to bring over a figure known as "Mr. Secretary", despite Fringe's attempts to stop them. Peter, from this action, deduces that he is from the parallel universe, and furious at Walter for hiding this information, leaves on his own. While hiding in the Pacific Northwest, Peter meets Mr. Secretary - Walternate, his true father, who offers to take him back to the parallel universe, which Peter accepts. Olivia and Walter are alerted by September that Walternate plans to use Peter to initiate the operation of a strange device that threatens to destroy the prime universe, and the two launch a rescue attempt. In the parallel universe, the find that it suffers from singularities caused by Walter's crossing in 1985, forcing Walternate's Fringe team to use an amber-like substance to surround and quarantine such areas, irregardless of innocent lives trapped within. They meet with William Bell, and Walter and Bell resolve their past differences. Olivia faces off against her doppleganger, "Fauxlivia", who works for Walternate in the Fringe Division under the U.S. Secretary of Defense; she is able to recover Peter, who has seen the device and recognized that it reacted only to his biology, and wants nothing of it, willing to return with the others. As Olivia, Walter, and Peter attempt to return, they are engaged by Fauxlivia and others in the Fringe Division. Bell sacrifices himself to provide energy into a device to allow the three to cross over, but none of them are aware that Fauxlivia has secretly switched places with Olivia under Walternate's orders, while Olivia is captured and held in a secured facility by Walternate. Anna Torv- Olivia Dunham/Alternate Olivia Joshua Jackson- Peter Bishop John Noble- Walter Bishop/ Alternate Walter Jaskia Nicole- Astrid Farnsworth/ Alternate Astrid Lance Reddick- Phillip Broyles/ Alternate Phillip Blair Brown- Nina Sharp Kirk Acevedo- Charle Francis/ Alternate Charlie A New Day In The Old Down Night Of Desirable Objetcs Fracture Momentum Deferred Dream Logic Earthling Of Human Action August Snakehead Grey Matters Unearthed Johari Window What Lies Below The Bishop Revival Jacksonville Peter Olivia. In The Lab. With The Revolver The Man From The Other Side Brown Betty Northwest Passage Over There Part 1 Over There Part 2